Is a double price gap normal between plastic box manufacturer quotes?

Answer: Not for one drawing, though 30%–40% is common: wall thickness, virgin ratio and buried tooling. Ask for the five-line breakdown.

Can a 500 piece MOQ drop to 100 for a trial?

Answer: Yes, with a 15%–25% surcharge and tooling paid in full. Buying an existing model first is cheaper.

Pay tooling upfront or amortise it?

Answer: Upfront below 1000 pieces, amortised above 3000, with recovery stop and ownership stated.

From which date does lead time run?

Answer: From signed sample approval, not from the order date.

What should a buyer bring to an audit?

Answer: The drawing with wall thickness, pallet data and the sampling plan. Two hours on the floor is enough.

Plastic Box Manufacturer: Quotes, MOQ and Lead Times

Quick answer: A plastic box manufacturer should quote in five separate lines — resin, moulding, tooling, hardware, packing — and the contract should fix MOQ, tool ownership and dated delivery milestones. Comparing unit prices alone costs more once the gaps are filled in.

How a Plastic Box Manufacturer Structures a Quote
MOQ and Tooling Amortisation
Capacity and Lead Time Arithmetic
What a Factory Audit Should Measure
Locking Price, Delivery and Acceptance
FAQ

1. How a Plastic Box Manufacturer Structures a Quote

A large case never has one unit price. Ask the plastic box manufacturer to split the figure into resin, moulding, tooling, hardware and packing, then argue line by line. Two quotes for one 600×400×340 mm envelope can differ by 40 yuan a piece, driven by wall thickness and regrind ratio.

Resin is priced on net weight plus sprue loss, runners at 8%–12% of shot weight. A case with 3.2 mm walls weighs 4.6 kg, so each 1000 yuan per tonne move shifts the piece cost by 4.6 yuan.

Cost line	Basis	Share of a 600×400×340 case	To negotiate
Resin	Net weight plus sprue	62%	Fix PP grade, cap regrind
Moulding	Rate × cycle ÷ cavities	14%	Verify tonnage, cycle
Tooling	Tool price ÷ first order	9%	Stop at recovery
Hardware, packing	Latches, valve, bag, pallet	15%	Name material, size

Tooling is the line most often charged twice. A 186,000 yuan deep-draw tool costs 372 yuan per case across a 500 piece first order and 62 yuan across 3000. Either the buyer pays once and owns the tool, or it is amortised until recovered, never both.

2. MOQ and Tooling Amortisation

For large cases, MOQ is a capacity question. A 2500 t press needs six hours for a tool change plus four hours of purging and heating, so the tool only pays while it stays mounted. That is why a standard large model starts at 500 pieces, with a first order near 800 and a 15%–25% surcharge below 300.

Plastic box manufacturer: olive case standing open, egg crate foam filling the lid, clear boxes in foam cutouts, rubber handle on the front wall

Tooling terms need a stamped serial, a trial allowance and ownership: five working days, three T1 samples, two modification rounds, ownership on payment, use rights kept by the factory.

First order	Tooling per piece	Effect on cost
300 pcs	620 yuan	+22%
500 pcs	372 yuan	Baseline
3000 pcs	62 yuan	−4%

3. Capacity and Lead Time Arithmetic

Lead time is arithmetic. One 2500 t machine on a 210 second cycle over 22 effective hours yields 377 pieces a day; four of twelve presses can take the large tool, so output reaches 1500. An order of 5000 pieces is four days of moulding, yet the quoted lead time is 25 days, because the queue and the hardware delivery sit in between.

Ask the plastic box manufacturer for dated milestones: tool at 45 days, trials at 5, sample approval at 3, production at 25, palletising at 2. The milestone that slips is modification after trial, and one re-cut costs seven days. A 1200×1000 mm pallet holds 24 cases upright, 48 in two tiers.

4. What a Factory Audit Should Measure

An audit is not a showroom tour. Check the machine list against the running rate, the resin store with grades and regrind apart, the tool rack with numbers and rust protection, and the finished yard with stacking height. If five of twelve presses run steadily, a large order will be subcontracted and wall thickness control leaves your sight.

Plastic box manufacturer: long olive case on a galvanised wire shelf, vertical ribs and four black draw latches, grey racking behind

Three settings tell you enough: drying at 80 °C for two hours, mould temperature at 60 °C, holding pressure on the machine card. An ultrasonic gauge should read 3.0–3.4 mm against a 3.2 mm nominal. Inspection terms need numbers: AQL 2.5 for appearance, AQL 4.0 for function, GB/T 2828.1 level II, so 50 pieces from a 500 piece lot, plus 48 hours of salt spray.

5. Locking Price, Delivery and Acceptance

Only the contract annex is enforceable, and a plastic box manufacturer rarely likes changing it. Write price in three parts: unit price with breakdown, validity of 15 days, and a resin clause that recalculates quarterly once PP moves beyond plus or minus 5%.

Delivery carries dates and a penalty: tool at 45 days, first article at 3, production at 25, and 0.3% of contract value per day late, capped at 5%. Acceptance covers the sampling plan, rework and freight when a lot fails, rejection after two consecutive failures, and confidentiality of drawings and tooling.

Conclusion

Three items decide real cost: resin basis, tooling recovery and the production slot. Split the quote into five lines, fix MOQ and tool ownership, and break delivery into dated milestones before signing anything with a plastic box manufacturer.

This article discusses only the container (case body) side of specifications and design intent, and does not cover any handling, loading or use of the contents.